20275
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Issue 6635: Removing class does not remove class tag
http://code.google.com/p/pharo/issues/detail?id=6635
Issue 6636: Review over RPackage system integration tests
http://code.google.com/p/pharo/issues/detail?id=6636
Issue 6461: [BUG]: Bogus package creation
http://code.google.com/p/pharo/issues/detail?id=6461